Not graduating from college in 4 years could cost students $300,000

A bank employee counts U.S. dollars at the headquarters of the Korea Exchange Bank March 12, 2003 in Seoul, South Korea.

Chung Sung-Jun

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Completing your bachelor’s degree in six years instead of four could cost you nearly $300,000 when factoring in tuition, loan interest and forgone income and retirement savings, according to a new study from NerdWallet.

NerdWallet calculated both real costs and opportunity costs to determine how much an extra year or two in college would cost the average student at public and private institutions. Real costs included out-of-pocket tuition and the interest paid on student loans over a standard repayment period of 10 years. Opportunity costs factored in forgone entry-level income as well as retirement savings compounded over 45 years, based on standard annual returns.

Here’s what the study found:

Taking one extra year to complete a bachelor’s degree would cost:

$147,026 at a public college, including $18,598 in tuition and interest on loans, $46,355 in missed income and $82,074 in compounded retirement savings.

$155,244 at a private college, including $26,815 in tuition and interest on loans, $46,355 in missed income and $82,074 in compounded retirement savings

Taking two extra years to complete a bachelor’s degree would cost:

$282,691 at a public college, including $37,456 in tuition and interest on loans, $94,353 in missed income and $150,882 in compounded retirement savings.

$298,995 at a private college, including $53,760 in tuition and interest on loans, $94,353 in missed income and $150,882 in compounded retirement savings.

To learn more about NerdWallet’s results and methodology, read the full study.